Further studies to investigate the pathogenesis of fever are planned in the following areas: 1) Mechanism of EP production in vitro by antigen-antibody complexes. 2) Mechanism of tolerance to fever in rabbits and guinea pigs desensitized to protein antigens. 3) Role of activator and suppressor T cells in release of an EP-producing lymphokine from phagocytic cells (monos and/or PMN's). 4) Further studies of pyrogenic factors in purified flu virus (ongoing project with Dr. Edwin Kilbourne, Professor of Microbiology at Mount Sinai Medical School). 5) Studies of the oxidative metabolism and EP production of leukocytes from patients with Anorexia Nervosa (in collaboration with Richard K. Root). 6) Studies of the effects of purified human MIF (prepared by Lutz Block, a visitor from the Max Planck Institute) on mononuclear cell metabolism and pyrogen production.